Process for the impregnation treatment and eventual sterilization of cocoa seeds or beans with water or alkaline solutions

ABSTRACT

A PROCESS FOR IMPREGNATING A SOLID VEGETABLE SUBSTANCE, SUCH AS COCOA SEEDS OR BEANS, WITH AN AQUEOUS FLUID, SUCH AS WATER OR AN ALKALINE SOLUTION WHEREIN THE VEGETABLE SUBSTANCE IS SUBJECTED TO VACUUM ACTION IN A SUITABLE ENVIRONMENT FOR A SELECTED PERIOD OF TIME, AND IS THEN MIXED WITH THE IMPREGNATING FLUID IN AN ENVIRONMENT MAINTAINED AT A PRESSURE OF AT LEAST ONE ATMOSPHERE AND A TEMPERATURE OF 120*C. OR MORE (STERILIZATION TEMPERATURE). THE IMPREGNATED SUBSTANCE IS THEN RAPIDLY DRIED IN AN ENVIRONMENT AT A PRESSURE WHICH IS LESS THAN ONE ATMOSPHERE.

' Filed D80. 2, 1969 Dec. 11, 1973 c. TARALLI ETAL 3,778,519

PROCESS FOR THE IMPREGNATION TREATMENT AND EVENTUAL STERILIZATION OF COCOA SEEDS OR BEANS WITH WATER OR ALKALINE SOLUTIONS 2 Sheets-Sheet 1 INVENTORS CLAUDID TARAVLLI sue srmm ATTORNEY 1973 I c. TARALLI ETAL 3,778,519

' PROCESS FOR THE IMPREGNATION TREATMENT AND EVENTUAL STERILIZATION OF COCOA SEEDS OR BEANS WITH WATER OR ALKALINE SOLUTIONS Filed Dec. 2, 1969 2 Sheets-Sheet 2 INVENTORS cut/ 0 TARALLHELIO STEFAN! ATTORNEY United States Patent 3,778,519 PROCESS FOR THE IMPREGNATION TREATMENT AND EVENTUAL STERILIZA'I'ION OF COCOA SEEDS OR BEANS WITH WATER OR ALKALINE SOLUTIONS Claudio Taralli and Elio Stefani, Milan, Italy, assignors to Carle & Montanari S.p.A., Milan, Italy Filed Dec. 2, 1969, Ser. No. 881,414 Claims priority, application Italy, Jan. 8, 1969, 848,426/ 69 Int. Cl. A23g N02 US. Cl. 426--352 5 Claims ABSTRACT OF THE DISCLOSURE This invention relates to a process and relative apparatus for the impregnation treatment and eventual sterilization of a substantially solid substance, such as cocoa seeds or beans, with a fluid, such as water or alkaline solutions.

For example, it has been known for some time that by treating cocoa seeds or beans with water or various alkaline solutions, an improvement in their color, a diminution of free acid, and a better suspension of cocoa powder in drinks are obtained by such processes.

The results of the treatment are greater the more complete the impregnation is of the vegetable fibres. With the processes used up to now, this impregnation is very slow and incomplete.

Furthermore, the successive operation of drying in order to eliminate water after treatment is long and costly.

SUMMARY OF THE INVENTION The present invention provides a process for the impregnation treatment of a substantially solid substance with a fluid, and includes the step of subjecting the substantially solid substance to vacuum action in a suitable environment for a selected period of time. Then, the substantially solid substance is mixed with the fluid in a suitable impregnating environment at a pressure of at least one atmosphere. Thereafter, the impregnated substantially solid substance is rapidly dried in an environment at a pressure which is less than one atmosphere.

The present invention also provides an apparatus for carrying out an impregnation treatment, wherein the apparatus includes a hopper for holding the substantially solid substance to be impregnated, and a tank containing the impregnating fluid. A container is provided which has a cylindro-conical shape for receiving the substantially solid substance to be impregnated. The container is provided with suitable vacuum type valves by means of which the container is connected to the hopper and to the tank. The container is also provided with means for obtaining 3,7 78,519 Patented Dec. 1 1, 1 973 ice and maintaining internally a predetermined degree of vacuum. The container is also provided with heating means for obtaining and maintaining a temperature suitable for the treatment of the substantially solid substance. The container also has suitable means for stirring the substantially solid substance and impregnating fluid. The container is provided with an opening at its base which is closed by an airtight valve by means of which the treated product may be discharged by gravity.

Although the invention may be employed for impregnating any substantially solid vegetable substance with a fluid, it is especially suitable for impregnating foodstuffs, such as cocoa beans, with water or an alkaline solution.

The main object of this invention is that of obviating the defects and disadvantages of systems presently used for such impregnation treatment, by means of a process which ensures deeper penetration of the water or alkaline solution into the inside of the vegetable fibres to be impregnated, thus conferring better results from the point of view of the successive processing of the cocoa for the reasons mentioned. Such systems presently used for such impregnation treatment are disclosed by German Pats. 509,206, 730,662, 745,398, 830,280, 838,244 and 955,647, and Austrian Pat. 124,048.

A further object of the invention is to provide an apparatus which allows elimination of the greater part of the water at low temperature and reduced pressure at the termination of impregnation treatment, and thereby considerably shortening the drying time.

Finally a further object of the invention is that of providing an apparatus which, in addition to carrying out the impregnation of the cocoa as previously mentioned, allows the raw materials to be subjected to a process of sterilization, thus obviating an obvious deficiency in the field of preparation of cocoa and its derivatives.

These and other objects are attained by the process for impregnation treatment of cocoa seeds or beans according to the present invention, in which the cocoa seeds or beans to be impregnated are previously subjected to vacuum action in a suitable environment where impregnation at atmospheric or higher pressure is successively carried out, and at the end of the treatment obtaining rapid drying with the use of a suitable pump which restores the low pressure environment.

The novel apparatus allows sterilization of the product to be obtained by raising the temperature inside the container to at least about C.

One possible apparatus or means for carrying out the process comprises a cylindro-conical container in the inside of which the vacuum can be created by means of a suitable pump, and whose external walls are surrounded by a coil heated by steam or the like, while a special rotating scraper stirrer permits uniform mixing together of liquid and solid, the whole assembly being provided with suitable valves.

BRIEF DESCRIPTION OF THE DRAWINGS The invention is described in detail hereinafter with reference to one embodiment of the treatment means given by way of example and illustrated in the accompanying drawings, in which:

FIG. 1 shows diagrammatically one embodiment of an entire treatment apparatus including two containers;

FIG. 2 shows an axial section through one of the containers in which the heating coil has been omitted for greater clarity;

FIG. 3 is a horizontal sectional view of the container through the line 3--3 of FIG. 2.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION Referring to the accompanying drawings, the flowsheet of the plant or apparatus shown in FIG. 1 comprises two treatment containers constructed according to the present invention. For the purpose of obtaining continuity of production, when one container is carrying out treatment the other is in the discharge phase, and vice versa.

In FIG. 1 the reference letter A indicates a hopper into which a weighed quantity of a substantially solid substance, such as cocoa seeds or beans, is loaded and the reference letter B indicates a tank which contains an impregnating fluid, such as water or alkaline solution. Both the hopper A and the tank B are connected to the treatment apparatus or container C with the interpositioning of valves 1 and 2, respectively, which are vacuum tight.

The treatment apparatus or container C may, for example, consist of a stainless steel container having a substantially cylindro-conical form with its upper base closed by a cover 3 of flanged elliptical profile, suitable for withstanding vacuum and at least two atmospheres pressure.

In the upper zone of each container C, a connection with a duct 4 is provided which is connected to a suction pump (not shown) and interrupted by a valve 5.

A coil 6 of semi-circular cross section is provided, wound in the form of a spiral on the external wall of each container C and fed by a supply of steam (not shown) by way of a duct 7 and a valve 8. Each of the two coils 6 in the plant or apparatus shown in FIG. 1 is provided with an automatically operating valve 9 for the discharge and removal of condensate which can be discharged by way of a single duct 9a.

Inside each container C there is a stirrer 10 which may, for example, consist of a steel ribbon formed as a spiral of large pitch. The stirrer 10 provides or guarantees delicate but intense movement of the product. A scraper 11 made of synthetic material may be connected to the stirrer 10 and may be arranged adhering to the cylindro-conical internal wall, and therefore has a shape similar to the two generating lines of the cylinder and the cone.

The stirrer 10-scraper 11 combination is driven by way of a shaft 12 of a worm reduction unit 13 by a motor 14, the whole drive assembly being arranged on the summit of the cover 3 of the container C.

On the open bottom of the container C there is a valve 15 for discharging the treated material. A pivot or counter shaft 12a supports the spiral ribbon stirrer 10 at the bottom.

The treatment process, as used for cocoa beans or seeds, may proceed in the following manner.

A weighed quantity of cocoa bean is placed in the hopper A suflicient for loading each treatment container C. At the same time, water or an aqueous solution of alkaline substance is placed in the tank B in the quantity and strength suflicient for the degree of treatment desired.

n opening the valve 1 of one of the two containers C the cocoa bean is introduced into the container. Then the valve 1 is closed vacuum tight, and the suction or vacuum pump (not shown) aspires or removes the air through the associated duct 4 with the valve open. When the desired degree of vacuum has been attained, the valve 5 is automatically closed and the pump stops. The product then remains in this environment for a certain or selected period of time (variable) under these conditions of very low pressure.

The water or alkaline solution is then introduced into the co tain r C whi e maintaining the pressure in the container C is increased to at least one atmosphere, and the corresponding stirrer 10 with its affixed scraper 11 enters into operation thereby giving rise to an intimate mlxing of the liquid and cocoa beans.

At the same time, heat is applied to the external wall of the container C by feeding the associated coil 6 with steam, until the desired temperature is attained internally.

The length of impregnation treatment cannot be established precisely as it is a function of various factors, such as the weight of the cocoa to be treated and, consequently, the capacity and volume of the apparatus, its degree of filling, the degree of granularity of the beans themselves, their initial humidity conditions, etc. Therefore, the length of impregnation may be determined by a trial and error method for different vegetable substances and quantities thereof.

At the end of the impregnation treatment, the water becomes superfluous and is eliminated (partially or completely) by evaporation at reduced pressure with the aid of the aforementioned vacuum pump, thus accelerating drying.

The treated and dried product is then discharged by opening the valve 15 of the container C in operation, and is then passed to the next process.

When sterilization of the cocoa bean is desired in addition to the impregnation by water or alkaline substances, it is sufiicient to raise the temperature inside the apparatus to about C. during the heating phase for the time necessary for this purpose.

When the time considered sufl'icient for impregnation and sterilization has elapsed, the suction or vacuum pump is put into operation. This creates better conditions for removal of water from the bean and, consequently, for rapid drying of the treated product.

What is claimed is:

1. A process for the impregnation treatment of a substantially solid vegetable substance with an aqueous fluid prior to the subsequent treatment thereof, comprising the steps of:

subjecting said substantially solid vegetable substance to vacuum action in a closed vacuum tight environment for a selected period of time;

introducing said aqueous fluid into said closed vacuum tight enviroment;

increasing the pressure in said closed environment to at least one atmosphere; mixing said substantially solid vegetable substance with said aqueous fluid in said closed vacuum tight environment at a pressure of at least one atmosphere;

simultaneously with said mixing step, heating said solid vegetable substance and said aqueous solution in said closed environment to cause impregnation of said solid vegetable substance by said aqueous fluid;

and rapidly drying the impregnated substantially solid vegetable substance in said closed environment at a pressure which is less than one atmosphere.

2. A process characterized in accordance with claim 1, wherein said substantially solid vegetable substance includes cocoa seeds or beans, and including the step of obtaining rapid drying of the impregnated cocoa seeds or beans with the use of a suitable pump which restores a low pressure environment.

3. A process characterized in accordance with claim 2, wherein sterilization of the product is obtained by raising the temperature to at least substantially 120 C. during said heating impregnation step, and wherein said sterilization operation is carried out in the closed environment and at a pressure greater than atmospheric pressure.

4. A process characterized in accordance with claim 1, including the step of sterilizing said impregnated substantially solid substance by raising the temperature to at least substantially 120 C. during said heating impregnation step, and wherein said sterilization step is carried out in the closed environment and at a pressure greater than atmospheric pressure.

5. A process characterized in accordance with claim 1, wherein said substantially solid substance to be impregnated includes cocoa seeds or beans, said impregnation fluid includes water or an aqueous solution of an alkaline substance, and including the step of sterilizing the impregnated cocoa seeds or beans by raising the temperature in the vicinity of said cocoa seeds or beans to at least substantially 120 C. during said heating impregnation step, and wherein said sterilization step is conducted in the closed environment and at a pressure greater than atmospheric pressure.

6 References Cited UNITED STATES PATENTS 3,223,021 12/ 1965 Osswald 9968 X 341,759 5/1886 Lobeck 9926 3,219,461 11/1965 Lamb 99204 X S. LEON BASHORE, Primary Examiner R. H. TUSIHIN, Assistant Examiner US. Cl. X.R. 99472; 426-459 

